Research will be directed in three areas during the coming year. Studies will be carried out to delineate the best protective mechanism in endotoxin-induced post-partum acute renal failture (Shwartzman reaction). This will involve the use of heparin and/or antiplatelet agents to interrupt the consumption coagulopathy and prevent morphologic desposition with endotoxin. Renal function will be evauated both at the clearance and micropuncture levels and compared to animals which have not received such pre-treatment. In addition, various blocking agents of the renin angiotensin system, thromboxanes, catecholamine and sympathetic nervous system will be used to find the effective selective blocking agent of the vasoconstrictor mechanism demonstratedin this disease process. Work will be continued to idetify an immunologically detectable material in tubular casts in norepinephrine-induced acute renal failure. It is planned that the detection of this substance may allow the early identification of patients that will suffer acute renal failure following a hemodynamic insult. The third major area of investigation will be to examine the segmental handling of sodium and water in both oliguric and polyuric forms of actue renal failure. It is planned to study at what site in the nephron the differences in handling of these substances occur that may account for the different clinical features. These studies will involve collection and analysis from the proximal tubule, the loop of Henle, distal tubule and base and tip of papillary collecting ducts.